Advances in audio technology, such as the introduction of audio playback systems including more and more speakers, have significantly improved the listeners' experience in modern theaters and dance clubs. In the past, surround sound offered a significant improvement over stereo sound by introducing audio that played on all sides of the listener in a two-dimensional audio experience. Multi-dimensional audio systems improved surround sound by allowing media producers to add a height component to sounds in media contents. Today, object-based audio is further improving the listeners' experience.